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deknight - Just checked the Rotora catalog online and they only list calipers for 355x32 rotors and larger. And they don't list a 4 pot for the fronts of our cars (or the e46 M3). Is yours using evosport carriers? Are the pads custom thicker ones too?

I have been researching caliper only kits for our cars and was looking at the Wilwoods from UUC. Rotoras seem like a good alternative too though and hence the questions.

deknight - Just checked the Rotora catalog online and they only list calipers for 355x32 rotors and larger. And they don't list a 4 pot for the fronts of our cars (or the e46 M3). Is yours using evosport carriers? Are the pads custom thicker ones too?

I have been researching caliper only kits for our cars and was looking at the Wilwoods from UUC. Rotoras seem like a good alternative too though and hence the questions.

Thanks.

I will find out the exact part numbers for you. You can always email brad@evosport.com and he can also get you the information. I do not believe there is anything custom on them. The carriers are standard for their set as far as I know.

Thanks. BTW, what pads are you running? Are popular pads like the Hawk HT10s or Pagid Yellows avaialble for these calipers or are we sort of stuck with what Rotora offers?

I am running Raybestos ST43 pads. These pads rock!!! Evosport goes an entire season on one set of pads!! They squeellll super bad but they work amazing!

They do offer alot of pad choices. but i would not use any other pad on the track! And the pad change takes seconds per wheel after the wheel is off. So when i put the street tires back on I just replace the track pads with street pads and I am good!

deknight - Just checked the Rotora catalog online and they only list calipers for 355x32 rotors and larger. And they don't list a 4 pot for the fronts of our cars (or the e46 M3). Is yours using evosport carriers? Are the pads custom thicker ones too?

I have been researching caliper only kits for our cars and was looking at the Wilwoods from UUC. Rotoras seem like a good alternative too though and hence the questions.

Thanks.

You are looking under the big brake kits, if you look under caliper only kits they will be there. The Rotora is in a different league than the other kits you mentioned.

BTW, we can now do the Rotora 6Piston race caliper on the CSL/ZHP size rotor for the e46 M3 and soon for the MZ4. This was announced at SEMA.

Quote:

Originally Posted by pal

Thanks. BTW, what pads are you running? Are popular pads like the Hawk HT10s or Pagid Yellows avaialble for these calipers or are we sort of stuck with what Rotora offers?

WE can supply you with nearly any pad you would like. For the street, the Rotora H2 is hard to beat (good stopping, low dust, ceramic). For the track, there is nothign I have found to be better than the ST43.

Quote:

Originally Posted by Palantirion

-As far as I know Rotora, Brembo and Stoptech all use the same pad size with their 4-piston calipers. Deknight is running a pad that I am not familiar with, and I'm sure he'll elaborate.

Not quite true. While the pads are similar, there are slight differences that prevent you from taking a brembo fit pad and putting it in the 4P Rotora caliper. Some do try to do this, but it requires quite a bit of grinding and they are still not perfect.

Please feel free to ask any questions.

BTW, as deknight mentioned, we use Rotora now on all the track cars. We did extensive testing and found the cars to be more stable under braking and faster around the track as compared to other brands (primarily tested against Brembo). The main reason is the far lower rotating mass and unsprung weight with the caliper only kits. We are using these on our 500+whp turbo e46 M3 race cars too! An added bonus is the cost of replacements for the caliper only kits is far less than a big brake kit. While bigger may look better, it is not necessarily the case that it IS better.

deknight - Just checked the Rotora catalog online and they only list calipers for 355x32 rotors and larger. And they don't list a 4 pot for the fronts of our cars (or the e46 M3). Is yours using evosport carriers? Are the pads custom thicker ones too?

I have been researching caliper only kits for our cars and was looking at the Wilwoods from UUC. Rotoras seem like a good alternative too though and hence the questions.

I was gonna ask that same question.
In all fairness, it wouldn't be an apples to apples comparison even if they did have charts...
(1) because Brembo doesn't offer a caliper only kit, and (2) they never tested the 355mm brake kits against each other.

Rather than taking this thread in the direction of arguing the different benefits of two entirely different products against each other, I think the point we can take from the OP's original post is that seat time + improved set up + confidence in your vehicle/modifications, goes a long way.

As far as the products themselves go, EvoSport has helped Rotora develop a product that was not yet available from other manufacturers, and at price point/performance level that they feel has value. The purpose, benefit, and performance value of a full BBK system are on an entirely different level and don't necessarily have a proper fit into this discussion at all.

I was gonna ask that same question.
In all fairness, it wouldn't be an apples to apples comparison even if they did have charts...
(1) because Brembo doesn't offer a caliper only kit, and (2) they never tested the 355mm brake kits against each other.

.

If EvoSport can provide graphs that shows that their Rotora system performed better then the Brembo set up on multiple tracks then its a brake system (apples) to brake system (apples) comparsion. They don't both have use bigger rotors in order for it be a comparsion. If Evo can make a better performing brakes set up with just a caliper conversion then I think that is an amazing feat. To me I don't care if its a "big" brake system or just a caliper upgrade.... all I am looking for is what provides the best performing brake system.

I am happy with the stock brakes, more so since I switched from Motul RBF600 to Brembo LCF 600+. However, on some track I still get fade towards the tail end of sessions. I have been working on changing my driving style a bit wrt brake usage, but that will only take me so far.

My reasons for a caliper only kit are lower cost, better cooling with the fixed aluminium caliper design compared to stock iron floaters, better pedal feel, lighter unsprung weight and hopefully keep using the 17" wheels in the winter with snows. Plus I think the stock rotors are very good and up to the task of HPDEs, for me anyways.

I am happy with the stock brakes, more so since I switched from Motul RBF600 to Brembo LCF 600+. However, on some track I still get fade towards the tail end of sessions. I have been working on changing my driving style a bit wrt brake usage, but that will only take me so far.

My reasons for a caliper only kit are lower cost, better cooling with the fixed aluminium caliper design compared to stock iron floaters, better pedal feel, lighter unsprung weight and hopefully keep using the 17" wheels in the winter with snows. Plus I think the stock rotors are very good and up to the task of HPDEs, for me anyways.

If I am not mistaken UUC makes both the AP and Wilwood caliper kits for our cars but I could be. I too have been totally happy with the stock brakes and my carbotech pads and fluid. There is also still things I can do to make the stock system even more effiecient. We gotta meet up soon bro!

I am happy with the stock brakes, more so since I switched from Motul RBF600 to Brembo LCF 600+. However, on some track I still get fade towards the tail end of sessions. I have been working on changing my driving style a bit wrt brake usage, but that will only take me so far.

My reasons for a caliper only kit are lower cost, better cooling with the fixed aluminium caliper design compared to stock iron floaters, better pedal feel, lighter unsprung weight and hopefully keep using the 17" wheels in the winter with snows. Plus I think the stock rotors are very good and up to the task of HPDEs, for me anyways.

"FADE" is not an issue to be solved only by upgrading the calipers. Fade, is a problem with heat dissipation, and heat dissipation does not improve dramatically with caliper.

As a friend of mine is fond of saying, if you're using your calipers to dissipate heat, you're in a lot of trouble. Upgrading to multiple piston, fixed caliper setup will help you with better pedal feel and a more consistent braking effort, plus the benefit of less unsprung weight, and unless the upgraded calipers has larger pad surface (it most likely won't unless you go all the way up to a 6 piston or more set-up...Look at the size of the BMW front pads) it will not alleviate your fade issues.

To cure your problem with fade, look at how heat is dissipated from the system. Cut away the dust shield on the hub, duct air directly into the center of the hub, or find a way to dissipate more heat via a better rotor design. Or upgrade to a big brake kit with them fixed calipers AND a larger, thicker rotor (by the way, larger diameter rotor may not always mean better. Thicker rotor actually goes a very long way in preventing fade).

By the way, if you're not ready to go BBK just quite yet, take a look at RacingBrake's replacement rotor. I mean, I thought BMW's floating 2 piece rotors were good, but the RB 2 piece rotors for the CSL/MZ4 is FREAKISHLY GOOD. And they're about 1.5 lbs lighter than BMW's OE rotors.

I'm helping them develop the rear rotors on the MZ4 as well. As soon as they've got a new casting done for the hub/ring assembly I'm suppose to get another set to test fit.

__________________

Quote:

"Bench racing" about track times driven by professionals are like a bunch of nerds arguing which Princess Leia is hotter, the slave Leia or the no-bra jail-bait Leia. No matter how compelling your argument is, the plain and simple fact is, none of you will EVER get to hit that.

"FADE" is not an issue to be solved only by upgrading the calipers. Fade, is a problem with heat dissipation, and heat dissipation does not improve dramatically with caliper.

As a friend of mine is fond of saying, if you're using your calipers to dissipate heat, you're in a lot of trouble. Upgrading to multiple piston, fixed caliper setup will help you with better pedal feel and a more consistent braking effort, plus the benefit of less unsprung weight, and unless the upgraded calipers has larger pad surface (it most likely won't unless you go all the way up to a 6 piston or more set-up...Look at the size of the BMW front pads) it will not alleviate your fade issues.

To cure your problem with fade, look at how heat is dissipated from the system. Cut away the dust shield on the hub, duct air directly into the center of the hub, or find a way to dissipate more heat via a better rotor design. Or upgrade to a big brake kit with them fixed calipers AND a larger, thicker rotor (by the way, larger diameter rotor may not always mean better. Thicker rotor actually goes a very long way in preventing fade).

By the way, if you're not ready to go BBK just quite yet, take a look at RacingBrake's replacement rotor. I mean, I thought BMW's floating 2 piece rotors were good, but the RB 2 piece rotors for the CSL/MZ4 is FREAKISHLY GOOD. And they're about 1.5 lbs lighter than BMW's OE rotors.

I'm helping them develop the rear rotors on the MZ4 as well. As soon as they've got a new casting done for the hub/ring assembly I'm suppose to get another set to test fit.

I suggested the Racingbrake rotor to Pal too as they look like a real nice design. Any idea on how they compare to the PF rotors? The RB's are a much better price then he PFs! So glad to see an M coupe owner is helping develop the kit. Keep us updated!

Thanks HACK and F360C (yes, we do need to meet up soon ... ). I did knock out the front "plates" in the bumper side air ducts and the Brembo fluid and Hawks have definitely improved the brake performance for my driving style on track. The Wilwood kit is a 6 pot front and 4 pot rear kit so I am guessing it will improve pad area- but I am not sold on a fixed piston caliper upgrade just yet- though pedal feel and lighter weight are definitely tempting.

I will see if BMW will give me a new set of front rotors this time as I am almost down to their wear limit. If not, then I may go with the Racing Brake floaters.

"FADE" is not an issue to be solved only by upgrading the calipers. Fade, is a problem with heat dissipation, and heat dissipation does not improve dramatically with caliper.

As a friend of mine is fond of saying, if you're using your calipers to dissipate heat, you're in a lot of trouble. Upgrading to multiple piston, fixed caliper setup will help you with better pedal feel and a more consistent braking effort, plus the benefit of less unsprung weight, and unless the upgraded calipers has larger pad surface (it most likely won't unless you go all the way up to a 6 piston or more set-up...Look at the size of the BMW front pads) it will not alleviate your fade issues.

To cure your problem with fade, look at how heat is dissipated from the system. Cut away the dust shield on the hub, duct air directly into the center of the hub, or find a way to dissipate more heat via a better rotor design. Or upgrade to a big brake kit with them fixed calipers AND a larger, thicker rotor (by the way, larger diameter rotor may not always mean better. Thicker rotor actually goes a very long way in preventing fade).

By the way, if you're not ready to go BBK just quite yet, take a look at RacingBrake's replacement rotor. I mean, I thought BMW's floating 2 piece rotors were good, but the RB 2 piece rotors for the CSL/MZ4 is FREAKISHLY GOOD. And they're about 1.5 lbs lighter than BMW's OE rotors.

I'm helping them develop the rear rotors on the MZ4 as well. As soon as they've got a new casting done for the hub/ring assembly I'm suppose to get another set to test fit.

The pad sizes are significantly bigger than stock. The fronts are about 1.5 times bigger than stock fronts and rears twice as big as stock rears. With a bigger pad it takes less effort to stop the rotor than a smaller pad so less fade. The pad type can play a big role in fade as well. The stocks pads will fade much more than a track pad.

The other problem with the stock caliper is that it is a 1 piston caliper and when lifting off the brakes the one side does not immediately come off the rotor so that makes it harder to cool down plus gives a sluggish feel. Even a 4 piston caliper (2 pistons on each side of the rotor) will release the pad immediately from the rotor, giving everything a chance to cool down quicker and cleaner trail braking.

You are right. A thicker rotor does help more than larger diameter from what i hear too.

Thanks for the info on the rotors i am really hoping to find something lighter and better than stock. I found the stoptech Aero rotor that matches our fronts on the Zeckhausen site.

I suggested the Racingbrake rotor to Pal too as they look like a real nice design. Any idea on how they compare to the PF rotors? The RB's are a much better price then he PFs! So glad to see an M coupe owner is helping develop the kit. Keep us updated!

I don't have direct experience with PF rotors, but anyone that I spoke with that has used them has nothing but praise for it. From all indications you can't lose with PF products.

Usually one of my favorite sayings, when it comes to anything automotive aftermarket is concerned, is you get what you paid for. In this case though, I'm not entirely certain the size of the company and the marketing efforts that goes into it doesn't have something to do with the price difference. All I can tell you is that, after 2+ years on the RB rotors on some of the hottest tracks and most brake intensive tracks on the West Coast, I have not had a single issue with the brake fading. Your mileage may vary, but I'm thoroughly impressed with this product.

And the rotor rings are barely showing any signs of use. I might be able to go another 20,000 miles and 3-4 more years of use, and two more sets of track pads.

__________________

Quote:

"Bench racing" about track times driven by professionals are like a bunch of nerds arguing which Princess Leia is hotter, the slave Leia or the no-bra jail-bait Leia. No matter how compelling your argument is, the plain and simple fact is, none of you will EVER get to hit that.

By the way, if you're not ready to go BBK just quite yet, take a look at RacingBrake's replacement rotor. I mean, I thought BMW's floating 2 piece rotors were good, but the RB 2 piece rotors for the CSL/MZ4 is FREAKISHLY GOOD. And they're about 1.5 lbs lighter than BMW's OE rotors.

I'm helping them develop the rear rotors on the MZ4 as well. As soon as they've got a new casting done for the hub/ring assembly I'm suppose to get another set to test fit.

I am curious about the weight differance over stock. When i was looking into my setup i was asking Palantirion for his opinion on a good setup. He loves his stoptech 4 pot front and rear (i drove it and i thought i was good too, just went another direction) but he said that his stoptech front rotors (which are bigger than stock 355 i believe) are 10 lbs. lighter than stock per rotor. Unless it was a typo is that because StopTech uses a differant compound than Racing Brake?

Just looked up the weight of the StopTech, they are light at 15.25 lbs (355x32). So they are alot lighter. Does the stock weight 19 lbs? If so that would be nearly 10 lbs. for both on weight savings.

The pad sizes are significantly bigger than stock. The fronts are about 1.5 times bigger than stock fronts and rears twice as big as stock rears. With a bigger pad it takes less effort to stop the rotor than a smaller pad so less fade. The pad type can play a big role in fade as well. The stocks pads will fade much more than a track pad.

The other problem with the stock caliper is that it is a 1 piston caliper and when lifting off the brakes the one side does not immediately come off the rotor so that makes it harder to cool down plus gives a sluggish feel. Even a 4 piston caliper (2 pistons on each side of the rotor) will release the pad immediately from the rotor, giving everything a chance to cool down quicker and cleaner trail braking.

You are right. A thicker rotor does help more than larger diameter from what i hear too.

Thanks for the info on the rotors i am really hoping to find something lighter and better than stock. I found the stoptech Aero rotor that matches our fronts on the Zeckhausen site.

There are obvious advantages to fixed caliper designs, there's no arguing that. I've been told/taught though, that your primary heat management in a brake system is the rotors. If you can manage heat properly through the rotors you'll solve 99% of issue regarding fade.

Quote:

Originally Posted by deknight

I am curious about the weight differance over stock. When i was looking into my setup i was asking Palantirion for his opinion on a good setup. He loves his stoptech 4 pot front and rear (i drove it and i thought i was good too, just went another direction) but he said that his stoptech front rotors (which are bigger than stock 355 i believe) are 10 lbs. lighter than stock per rotor. Unless it was a typo is that because StopTech uses a differant compound than Racing Brake?

I don't know what exactly Palantirion's brake set up is so I can only offer an educated guess. IF he is running a completely StopTech kit, the reason why his front rotor is significantly lighter than OEM and RB rotor is, there's LESS iron rotor ring and more aluminum HAT material on the StopTech rotor. Typically the sweep area on a BBK (except for the UUC kit that uses OEM sized rotors) is narrower and longer in shape, therefore the contact "ring" area on a BBK rotor can afford to be much shorter in shape, resulting in significantly less of the heavier iron in construct. So going all the way to a BBK set-up has significant merit in weight reduction vs. using BMW OEM system. Since the RB rotors are direct BMW OE replacement, the design is bound by the size of the sweep area on the rotor ring, and it's a MASSIVE sweep area and therefore massive ring. The fact that the RB rotors are 1.5 lbs lighter than OEM BMW rotors is actually quite impressive, since BMW ring hub is also lightweight aluminum on the 2 piece design.

There's nothing tricky to brake rotors. You can't really use a different "compound" per se. It's cast grey iron, or you have to go to the tricky carbon/ceramic mixture to save weight on the rotor (über expensive). I suspect, if Palantirion is running a complete StopTech system, not just a caliper upgrade and OE sized rotors, that the weight saving does indeed come from using a larger diameter ring hub therefore reducing overall size and mass of the iron rotor ring. And the larger diameter ring hub also allows for more air to enter the cooling vanes therefore the smaller heat sink mass is offset, offering cooling capacity similar if not better than OEM rotors.

__________________

Quote:

"Bench racing" about track times driven by professionals are like a bunch of nerds arguing which Princess Leia is hotter, the slave Leia or the no-bra jail-bait Leia. No matter how compelling your argument is, the plain and simple fact is, none of you will EVER get to hit that.

There are obvious advantages to fixed caliper designs, there's no arguing that. I've been told/taught though, that your primary heat management in a brake system is the rotors. If you can manage heat properly through the rotors you'll solve 99% of issue regarding fade.

I don't know what exactly Palantirion's brake set up is so I can only offer an educated guess. IF he is running a completely StopTech kit, the reason why his front rotor is significantly lighter than OEM and RB rotor is, there's LESS iron rotor ring and more aluminum HAT material on the StopTech rotor. Typically the sweep area on a BBK (except for the UUC kit that uses OEM sized rotors) is narrower and longer in shape, therefore the contact "ring" area on a BBK rotor can afford to be much shorter in shape, resulting in significantly less of the heavier iron in construct. So going all the way to a BBK set-up has significant merit in weight reduction vs. using BMW OEM system. Since the RB rotors are direct BMW OE replacement, the design is bound by the size of the sweep area on the rotor ring, and it's a MASSIVE sweep area and therefore massive ring. The fact that the RB rotors are 1.5 lbs lighter than OEM BMW rotors is actually quite impressive, since BMW ring hub is also lightweight aluminum on the 2 piece design.

There's nothing tricky to brake rotors. You can't really use a different "compound" per se. It's cast grey iron, or you have to go to the tricky carbon/ceramic mixture to save weight on the rotor (über expensive). I suspect, if Palantirion is running a complete StopTech system, not just a caliper upgrade and OE sized rotors, that the weight saving does indeed come from using a larger diameter ring hub therefore reducing overall size and mass of the iron rotor ring. And the larger diameter ring hub also allows for more air to enter the cooling vanes therefore the smaller heat sink mass is offset, offering cooling capacity similar if not better than OEM rotors.

That makes total sense about the hub size. Thanks for explaining that. So just because someone makes a 345x28 two piece rotor it may or may not fit our cars since the hub has to match the stock setup?

Or can you buy a total rotor setup (rotor and hat) that matches the same diameter size (345x28 front) and use that?

I don't have direct experience with PF rotors, but anyone that I spoke with that has used them has nothing but praise for it. From all indications you can't lose with PF products.

Usually one of my favorite sayings, when it comes to anything automotive aftermarket is concerned, is you get what you paid for. In this case though, I'm not entirely certain the size of the company and the marketing efforts that goes into it doesn't have something to do with the price difference. All I can tell you is that, after 2+ years on the RB rotors on some of the hottest tracks and most brake intensive tracks on the West Coast, I have not had a single issue with the brake fading. Your mileage may vary, but I'm thoroughly impressed with this product.

And the rotor rings are barely showing any signs of use. I might be able to go another 20,000 miles and 3-4 more years of use, and two more sets of track pads.

Holy Moly batman, are you saying you have been using the same set of rotors for over 2 years and they still have alot to go? How many events do you do in a year roughly?

That makes total sense about the hub size. Thanks for explaining that. So just because someone makes a 345x28 two piece rotor it may or may not fit our cars since the hub has to match the stock setup?

Or can you buy a total rotor setup (rotor and hat) that matches the same diameter size (345x28 front) and use that?

It depends. If you're using OEM calipers (and OEM pad sizes), you must take the rotor hat size and shape into consideration. If you're buying a completely system with caliper, caliper bracket, and rotors all designed to fit with each other, then the rotor hub size/design must match that of the new system, not necessarily the OEM rotor hub.

Quote:

Originally Posted by deknight

Holy Moly batman, are you saying you have been using the same set of rotors for over 2 years and they still have alot to go? How many events do you do in a year roughly?

Between 2006 and 2008 I was doing around 20 days per year. Since my daughter was born in 2008 I've been limited to about 6-8 days a year.

Rotor longevity is a sign of a well designed rotor if you ask me.

__________________

Quote:

"Bench racing" about track times driven by professionals are like a bunch of nerds arguing which Princess Leia is hotter, the slave Leia or the no-bra jail-bait Leia. No matter how compelling your argument is, the plain and simple fact is, none of you will EVER get to hit that.

I was gonna ask that same question.
In all fairness, it wouldn't be an apples to apples comparison even if they did have charts...
(1) because Brembo doesn't offer a caliper only kit, and (2) they never tested the 355mm brake kits against each other.

Rather than taking this thread in the direction of arguing the different benefits of two entirely different products against each other, I think the point we can take from the OP's original post is that seat time + improved set up + confidence in your vehicle/modifications, goes a long way.

As far as the products themselves go, EvoSport has helped Rotora develop a product that was not yet available from other manufacturers, and at price point/performance level that they feel has value. The purpose, benefit, and performance value of a full BBK system are on an entirely different level and don't necessarily have a proper fit into this discussion at all.

Hi Gary!

I know you are defending Brembo, but there is really no need or reason to in this case. Brembo are fantastic in some applications and fitments. As you know, we also use and sell Brembo and are in LOVE with the GTR brakes.

I also went to YOU first for a caliper kit and you guys said "NO WAY" so we found someone else to do it.

When you compare the Rotora caliper agains the 4P old style Ferrari F40 Brembo caliper in most GT kits, it is a non-starter in my REAL experience on the street and track with BMW's. If you want to compare agains the new Brembo 6P monobloc, that is a different story entirely as that is a great caliper (as is the new 6P Rotora monobloc).

It is fair to compare a 14" big brake kit to a caliper only kit with 13-13.5" OE rotors as this is the buying decision that most users realistically make. IN our findings in 4 years of racing on Rotora and 8 years of racing on Brembo, we could not be happier with the Rotora caliper only kits. The rotor size is more than ample to give the torque required. The problem with BMW brakes is the single piston caliper, not the rotor size. Further, the caliper only kti keeps your initial and replacement costs down. This is a true Win/Win.

Again, remember, I came to you first to do this!

Quote:

Originally Posted by F360C

If EvoSport can provide graphs that shows that their Rotora system performed better then the Brembo set up on multiple tracks then its a brake system (apples) to brake system (apples) comparsion. They don't both have use bigger rotors in order for it be a comparsion. If Evo can make a better performing brakes set up with just a caliper conversion then I think that is an amazing feat. To me I don't care if its a "big" brake system or just a caliper upgrade.... all I am looking for is what provides the best performing brake system.

We have data acquisition, but it was 4 years ago, and I would be hard pressed to find it. However, my customers in the two turbo cars we run have no budget. They would put on anything that worked better (short of spending the 20K on the Brembo GTR for club racing). They both had Brembo on previous cars and one on this chassis also. They are both more than happy with the change to Rotora, and they gained time on the track.

They have set track records at every track they go to, that is proof enough for me.

Quote:

Originally Posted by pal

My reasons for a caliper only kit are lower cost, better cooling with the fixed aluminium caliper design compared to stock iron floaters, better pedal feel, lighter unsprung weight and hopefully keep using the 17" wheels in the winter with snows. Plus I think the stock rotors are very good and up to the task of HPDEs, for me anyways.

YEP - and this is what you will get exactly!

Quote:

Originally Posted by The HACK

"FADE" is not an issue to be solved only by upgrading the calipers. Fade, is a problem with heat dissipation, and heat dissipation does not improve dramatically with caliper.

As a friend of mine is fond of saying, if you're using your calipers to dissipate heat, you're in a lot of trouble. Upgrading to multiple piston, fixed caliper setup will help you with better pedal feel and a more consistent braking effort, plus the benefit of less unsprung weight, and unless the upgraded calipers has larger pad surface (it most likely won't unless you go all the way up to a 6 piston or more set-up...Look at the size of the BMW front pads) it will not alleviate your fade issues.

To cure your problem with fade, look at how heat is dissipated from the system. Cut away the dust shield on the hub, duct air directly into the center of the hub, or find a way to dissipate more heat via a better rotor design. Or upgrade to a big brake kit with them fixed calipers AND a larger, thicker rotor (by the way, larger diameter rotor may not always mean better. Thicker rotor actually goes a very long way in preventing fade).

By the way, if you're not ready to go BBK just quite yet, take a look at RacingBrake's replacement rotor. I mean, I thought BMW's floating 2 piece rotors were good, but the RB 2 piece rotors for the CSL/MZ4 is FREAKISHLY GOOD. And they're about 1.5 lbs lighter than BMW's OE rotors.

I'm helping them develop the rear rotors on the MZ4 as well. As soon as they've got a new casting done for the hub/ring assembly I'm suppose to get another set to test fit.

You are right that it will not solve the problem 100%, but that is the biggest weak link in the BMW system. So changing the caliper is the first logical place to start IMHO as you get the biggest return on that investment.

I did not know about the RB's only the PFC's (which I did not see available for the Z4 chassis). The RB's might be a fantastic option for the caliper kit if you want the 2pc rotor set-up.

Quote:

Originally Posted by The HACK

I don't have direct experience with PF rotors, but anyone that I spoke with that has used them has nothing but praise for it. From all indications you can't lose with PF products.

Usually one of my favorite sayings, when it comes to anything automotive aftermarket is concerned, is you get what you paid for. In this case though, I'm not entirely certain the size of the company and the marketing efforts that goes into it doesn't have something to do with the price difference. All I can tell you is that, after 2+ years on the RB rotors on some of the hottest tracks and most brake intensive tracks on the West Coast, I have not had a single issue with the brake fading. Your mileage may vary, but I'm thoroughly impressed with this product.

And the rotor rings are barely showing any signs of use. I might be able to go another 20,000 miles and 3-4 more years of use, and two more sets of track pads.

I have sold the PFC rotors with caliper only kits for the e46 M3 and had great results from the customers!

I did not know about the RB's only the PFC's (which I did not see available for the Z4 chassis). The RB's might be a fantastic option for the caliper kit if you want the 2pc rotor set-up.

Hm...I could put you in touch with the owner/operator of RacingBrake and see if you guys can work out some sort of package for a Rotora caliper kit with RB 2 piece OE replacement rotors to be sold as a kit through EVOSport. Win/win all around?

Maybe it'll force Warren@RB off of his butt to make the rear two piece rotors. I know he's got something going on already but he's concentrating on the Corvette market.

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"Bench racing" about track times driven by professionals are like a bunch of nerds arguing which Princess Leia is hotter, the slave Leia or the no-bra jail-bait Leia. No matter how compelling your argument is, the plain and simple fact is, none of you will EVER get to hit that.